People v. Urziceanu
Court of Appeal of the Third District of California
132 Cal. App. 4th 747 (2005)
Michael Urziceanu (defendant) formed a marijuana growing-and-distribution cooperative, believing in good faith that California's Compassionate Use Act permitted the cooperative's activities and client reimbursement scheme. Charged with selling and conspiring to sell marijuana, he was repeatedly denied the chance to present his good-faith mistake-of-law defense and a related jury instruction; the jury acquitted him of the sales charge but convicted him of conspiracy, and he appealed the denial of the mistake-of-law defense as to conspiracy.
Whether a defendant may claim mistake of law as a defense where the mistake negates a material element of the charged offense, such as the specific intent required for conspiracy.